Shifting apparatus for an automatic transmission of a vehicle have a shift lever that extends from a bracket mounted on a body of the vehicle. The apparatus has a desirable shifting operation relative to an automatic transmission of the vehicle and can be achieved by operating the shift lever fore and aft. In such a prior art shifting apparatus for an automatic transmission of a vehicle, such as Japanese Laid-open Patent Publication No. 132908/1996, the swing motion of the shift lever, an “operating lever” in the reference above, is limited when it is in the parking position (P) or the neutral position (N). Here, a push knob is provided at the top end of the shift lever and a pin on a rod lock pin, a “detent rod” in the reference above, is adapted to be lowered by the push knob. The pin is inserted in an erroneous operation preventing window, a detent engaging portion in the reference above, formed on the side of the bracket.
The shift lever is structured in order to prevent erroneous shift lever operation by a driver. Thus, the pin engages the erroneous operation preventing window to limit the swing motion of the shift lever when it is in the parking position (P) or the neutral position (N). On the other hand, swing motion of the shift lever is allowed by pushing down the push knob to lower the pin together with a rod lock pin and thus to release the engagement of the pin and the erroneous operation preventing window. The window is formed with stepped portions at positions corresponding to those of the park (P) and neutral (N) positions and the pin can engage or disengage such a stepped portion.
However, a problem exists in the prior art shifting apparatus for an automatic transmission of a vehicle in that the freedom of design is not sufficient since the descending distance of the pin is uniformly determined only by the displacement amount of the push knob. This is due to the fact that the pin, adapted to engage the erroneous operation preventing window, is formed on the rod lock pin and thus the former pin and the latter pin are integrated. Due to design requirements of the shifting apparatus for an automatic transmission of a vehicle, sometimes it is required to provide a desirable displacement amount of the push rod. On the contrary, since the displacement amount of the push knob and the descending amount of the pin are uniformly formed in the apparatus of the prior art, the rod lock pin itself must be changed in accordance with each form of the shifting apparatus. Since it is impossible to use the rod lock pin of the prior art as is, and due to recent increasing need to reduce the displacement amount of the push rod, the manufacturing cost is also increased.